OYSTEIN ORE [1] has stated that the group of aut om or ph ismsof the lattice of all closure operators definable over the lattice ofsubsets of a set S is isomorphic, to the group of permutationsof S.The group of automorphisms of the lattice tP(L), whose elementsare the closure operators definable over a complete lattice L (1),has been studied by PH. DWINGER [2]. However, the assertion,contained in [2], of the existence of an isomorphism between thatgroup and the group of automorphisms of L, is not true, as oneconcludes from the following example: let L be the chain
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